Modem industrial processes are becoming increasingly automated and complex. Such processes, whether involving the smelting of steel or the generation of nuclear power, are typically overseen from a centralized location by a process engineer or operator, who monitors data from hundreds, or even thousands, of sensors distributed throughout a facility. Sensors measuring voltage, current, power consumption, magnetic or electric field strength, temperature, pressure, humidity--the list is virtually endless--can be part of a modern process control system. Sensor data is used to evaluate the suitability of raw materials, provide feedback data during processing and manufacture, control valves and process flows, ensure the quality of manufactured products, and generate alarms. In particular, sensors can be used to gather data indicative of an alarm state in an process control system.
When an alarm occurs, considerable demands are placed on the process operator, who, confronted with a vast array of data from a vast array of sensors, must respond quickly and effectively to ensure safe and economical operation of the facility. Optimally, when an alarm occurs the operator is immediately alerted. Next, the operator ascertains the location, purpose and significance of the sensor. Typically, there are thousands of pages of documentation describing the operation of the industrial process in question and describing the purpose and significance of the various sensors. After locating and consulting the appropriate portions of the documentation, and perhaps viewing data from other sensors, the operator institutes proper corrective action. The actual scenario, however, is not always optimal, and the operator's job is at times difficult.
In an earlier era, of simpler, less automated industrial processes, an annunciator wall panel often informed operators of alarms. Individual sensors were essentially hard wired, via relays or other simple circuitry, to individual lamps placed at appropriate locations on a wall-sized schematic of the process. Sensor data out of an acceptable range illuminated a light and sounded a horn. However, technological advances, particularly the advent of computers, have greatly increased the complexity of most industrial processes, as well as increased the burden on the operator charged with oversight of the process. In many cases, the old annunciator panel wall is obsolete and relatively inflexible.
Technological advance has also improved the tools used by the process operator. Video displays run application programs that can, for example, graph process data, display a process graphic (a schematic representation of a portion or of all of an industrial process) or perform a keyword search through documentation. However, not all the tools are significantly improved: the hardware annunciator keyboard (HAK) remains. The HAK is composed of a numeric keypad with adjacent rows of illuminable lights, and can be described as essentially a shrunken version of the annunciator wall panel. An occurrence of a sensor alarm causes a horn to sound and illuminates a key associated with that alarm. The operator acknowledges the alarm and silences the horn by pressing the illuminated key.
The present HAK does not optimally address the needs of an operator charged with overseeing a modern and highly automated modern industrial process. The existing HAK is bulky, costly to produce, difficult to reconfigure, and limited to a number of standard key formats. The HAK warns an operator of all alarms, regardless of severity, in the same manner--the same horn sounds, and one of several keys, all typically of the same color, illuminates. Adding alarm states to a process control system can require multiple hardware annunciator keyboards, as keys are not easily added to an existing keyboard, further adding to system costs.
Accordingly, a need exists for a more economical and versatile alarm interface that relatively quickly and effectively communicates alarm states, facilitates timely and proper corrective action, and complements the graphical tools for video display already at the operator's disposal.
It is an object of the invention to provide a more versatile keypad annunciator that allows an operator to manage more effectively and efficiently a modern complex industrial process control system.
It is a another object of the present invention to provide a keypad annunciator that more effectively presents alarm data.
It is a further object of the present invention to reduce the cost of producing a keypad annunciator.
An additional object of the invention is to provide an operator-configurable keypad annunciator that an operator may readily configure to better ensure acknowledgment and appropriate operator response to the occurrence of an alarm state.